weagant



Sept. 18 1923.

R. A. w

PROCESS AND APPARATUS FO Filed July 19 191'? EAG ANT R RECElVING RADIOSIGNALS 2 Sheets-Sheet 1 E] woe M102 4;} H 5 mfm ibq Sept. 18 1923.

R. A. WEAGANT PROCESS AND APPARATUS FUR RECEIVING RADIOSIGNALS Filed July 19 1917 2 Sheets-Sheet 2 Patented Sept. 18, 1923.

uurrsn STATES 1,468,060 PATENT OFFICE.

BOY ALEXAIYDER WEAGANT, OF BOSELLE, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO RADIO CORPORATION OF AMERICA, A CORPORATION OF DELA- WARE.

PROCESS AND API'ARATUS FOR RECEIVING RADIOSIGNALS.

Application filed July 19, 1917.

'1 '0 a]! whom it may concern.

Be it known that. l, llov ALEXANDER VB/\- GAN'I, a citizen of the United States, residing in the town of Roselle. in the county of Union, State of New Jersey, have discovered certain new and useful improvements in Processes and Apparatus for Receiving Radiosignals, oi which the following is a specititration.

My invention comprises a new method for the reduction of interference with radio conununication due to atmospheric disturbances variously known as static," strays or "Xs." and new apparatus for practicing the new method.

My invention, broad y considered, ma}; be 'arried out bv various arrangements of apparatus, those shown and described in the drawing :m-ompanying and forming a part of this specification lacing the preferred forms of apparatus.

lieterring to the drawing,

Figure l is a schematic diagram illustrating receiving apparatus embodying my invention. and adapted for use in practicing my improved process.

Figure t. illustratcs a modified arrangement, in which an alternative form of an tenna is employed. and in which a different arrangement of adjusting devices is used. As an additional feature. it includes a coupling neutralizing means.

Figure 3 shows the weterrcd disposition or relation of the receiving apparatus to the transmitting apparatus.

in the investigation of static disturbances, I have discovered that antcnna separated 'l'roin one another by considerable dist ances appear to be acted upon by such disturbances substantially simultaneously, the effect being as though such disturbances were caused by eleetromagnetic waves or ill]- pulses propagated pcrpcndicularly to the surface of the earth, and almost without horizontal components. The cll'cct. in other words. is as though these disturbances chietiv originated at a grcat height above the earth and had their horizontal components substantially neutralized. so that widely separate antennae. if on the same level, have disturlutnccs set up in them which occur simultanemisly.

l have reached this conclusion after nu merous tests which appear to admit of no Serial No. 181,458.

other explanation, but whether or not it is a correct. statement of the facts. find that by proceeding on this assumption and using a directional combination of separated antenna. as hereinafter described, I am able to very largely overcome the interference with reception caused by the most objectionable forms of atmospheric disturbances.

The disurhing causes do not behave as though possessed of either definite wave length or decrement, but set up in the antenna oscillations which have the frequency and thc decrement of the antennae themselves. and by suitable adjustments, I find it. possible to cause the electromotive forces, induced in two or more antennifihy the atoms phcric disturlmnces, to set up currents there in of the same wave length, decrement, and phase. so that by opposing their cll'ect on the detector circuit substantial neutralization may bc accomplished.

The ctl'ccts produced upon two such antcnnzc by signals will, however, be out of phase with one another, except when the signal is received in a line at right angles to a plane common to the antennae. This difference of phase will be greatest when the antennae are in a common plane which also passes through the point of origin of the signals.

I have found that with such an arrangement it is possible to cause the eti'ects pro duced in a. plurality of antcnnato be so coinlllllt'tl in a single circuit as to neutralize or combine ditl'crcntially the effects due to static and those due to signals coming in a direction at right angles to the plane of the anti-mac, while combining cumulatively the ctl'ccts of signals arriving in the common plane of the antennae, or from directions not too nearly at right angles thereto.

The difference in phase of the electrometivc Forces set up by received signal waves will also depend upon the distance of scparation of the etl'ectivc centers of the antennae measured in the direction of propagation of the waves.

In my own practice of the invention up to this time. I have found it desirable to bring leading-in wires from the antennas to a common point, preferably, but not necessarily, to the center of the antenna svstem. If an tcnnac of the ordinary open circuit type are employed, these leading-in wires act as part of the antennae in the absorption of energy from the signal waves, and thus the effective separation of the antennae becomes less than the actual separation of the elevated conductors. I have found that this disadvantage can be overcome by employing antennae in the form of vertical loops. I have found that a vertical loop antenna without earth connection, will have electromolive forces set up in it as a result. of atmospheric. disturbances, which appear to depend for a given horizontal dimension, upon the mean vertical separation of the horizontal portions of the loop from'one another. For example. if the loop is in the form of a rectangle having two of its sides horizontal, the magnitude of the effective electromotive forces set up appears to depend upon the vertical separation of the two horizontal sides.

On the other hand, the effect of a received signal on a single vertical loop antenna depends upon the direction from which the signal is received, and, for a given vertical dimension, upon the distance between the vertical sides.

The maximum effect for a given antenna is obtained when the plane of the antenna passes through the point of origin of the signal to be received, since the effective elec tromotivc force in such a loop depends upon the difference in phase of the effects in the two vertical sides of the antenna.

1 have found that it is possible to take advantage of these facts to substantially eliminate the above-mentioned effects of the leads, and secure an effective separation equal to the distance between the centers of the loops, if the two leading-in wires rom each of two such loops antennae are similarly situated with respect to earth. as for example, by being carried on poles at the same height above earth, so that the efi'ects upon the leads. both of atmospheric disturbance and of signal waves. will be neutralized. This is because the plane containing the leads is at right angles to the vertical oscillator from which the signals originate and no current is produced in them by said signal so long as its wave front, is vertical. My tests have shown. also, that these horizontal leads do not have-currents set up in them by static disturbances at all comparable to those set up in the antcnnic.

By employing two such antenna and coin ducting the lcadingin wires to a common point. advantageously. but not necessarily equidistant from the two. I am able. by combiliing the actions on the two loop antennae in-a single instrument or group of instruments. to oppose the cfi'ccts of static u on the two antcnmc. and thereby neutra ize them, while combining cumulatively the effects of thc signal. obtaining the full benefit of the separation of the antennas without any loss of effective separation. due to the action of the leads.

lly applying this method I have succccdcd in rec iving commercially readable trans atlantic signals through atmospheric dis turbanccs so powcrl'ul and continuous as to make it otherwise impossible cvcn to i'tcognize the existence of the dcsircd signal.

llel'erring to the arrangement shown in Figures 1 and 3 of the drawings, A A, rep resent two loop antcnnai. preferably in the same plane with one anothcr. and with the transmitting station T from which the desired signals are to be received, as shown in Figure 3, but it is not essential that this condition should be absolutely attained. Two pairs of leads B B extend from said antennae to a receiving station which may advantageously, but need not necessarily be located midway between the two antennae. These leads are preferably supported on poles. as shown in Figure 3. and should preterably be kept at the same distance from the earth as above noted. and the separation of the wires of each pair from each other may advantageously be the same.

Each of the leads B and B has included therein. preferabl but not essentially in each wire thereo suitable tuning inductanccs C from which connections. including variable capacity elcments. lead to any suitable apparatus in which the etlccts may be combined as above dcscribed. That shown comprises pairs of coils l) D to which the connections from coils C 't" are led. the circuit being completed in cach'case by a variable condenser indicatcd at E E. It will be noted that this gives a symmetrical arrangement, and this I have lound desirable for best results, but not essential to good results.

7 Instead of a single condenser for each antennai circuit located as shown. it may be located anywhere else in the lead wires. or two cont cnsers may be employed. one in each lead. seems to give the best results.

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A symmetrical arrungcmcnt The coils of each pair D D may be adjustable as to their separatidn. but they also operate well when wound togcthcr. The coils may be circular or rcctangular or other form.

\Vithin the space affected by coils l) D, and preferably rotatably mountcd on an axis parallel to the planes of coils D D. is a coil which in operation is subjected to the fields of force set up in the coils D l). and which is suitably conncctcd to the detecting and indicating circuits. By suitably connecting the coils and adjusting the angular position of the coil F. the effects due to the static disturbances neutralize or are com bincd differentially in the coil F. while the effects due to the signals combine to pro duce a. resultant current therein. In this ary magnetic field. alternating fition w gf the field'd'ue the interfering disturbances manner a nearly complete elimination of the most objectionable types of static disturbances is possible.

The electromotire forces produced in the two antennae by the static disturbances a pear to be as pointed out, substantially in phase, and by suitable adjustments of the constants of the circuit, the currents are also in phase. Their effect in the coils I) D is, therefore, to produce a magnetic field. having substantially a fixed direction. The offeets'ofthe received signal being to set up curi'iiiitsdifi'ering in phase, these currents flowingin the coils l) D will produce either a resultant rotating magnetic field or a Ithtionar magnetic field at right angles to tlilt procliiced by the static disturbances according to the phase difference between said currents. By locating the coil F in the plane of the magnetic field due t the static disturbances, the effect of the staliic disturb- Will be neutralized upon the coil F, while a resultant effect is produced. bythe desired signal. By rotating the cdll F in thisarran Inent, so that it passes from the ere its plane is parallel to that to the interfering disturbgnces to one at right angles therefrom, the interference will pass from a minimum to at maximum effect, since in the latter posiwould cumulatively affect the coil F.

If the difference in phase of the currents produced by the desired signals is not 180", then the position of the coil F. which gives maximum signal, will not, with this arrangement, be that of minimum interferencc rial. That shown, uicr cly illlllStl'lllZlOflf. is the circuit of my pending upbut' the position of minimum interference will still give a large percentage of the maximum attainable signal strength.

The separation of the antennae A A measured from center to center of the loops,

may be anything desired within cons derable limits, so ong as it be sullicie nt so that the difference in phase between the resultant electronwtive. force is appreciable and adequate to give a resultant magnetic (or electro-static) field, utilizable to create dctectalile signal currents, without reuuiringan impracticable degree of refinement of com struction or manipulation. The preferable separation is one-half of a wave length. since this results in currents due to the desired signals exactly opposite in phase. whereby.

vif the circuits are so arranged as to cause the effects of static to oppose. the Slllll'll effects will bl added to product a Sttllltllk in polarity. to act upon the coil l of the local circuit. If the separation be less than one-half of the wave length. the cticcts will he combin-d geometrically to form a resultant rotating field. which will be substantially uniform. if the separation is one quarter of the wave length, but will be a so-callcd elliptical field be understood by those skilled if the separation something different from one-quarter of the wave length, the greatest effect being produced when the plane of the coil F is at right angles to the direction of the major axis of the ellipse. 'lhezp'ri duction of a rotating tieldis merely incidental to the so-called gonionu-ter" arrange ment shown in Figure 2, wherein the coils D I) are at right angles and is not essential, but is an arrangement which I have found to work well in practice.

Thisarrangement, therefore, can be used as a direction finder, irrespective of its utility as a static interference eliminator, since the direction of origin can be located by observing the angular position of the coil F, re uired to give maximum signal strength. l rom the known separation of the antennae, the observed wave length and the .position of the coil 1 for maximum signal, the direction of transmission of the received signal can be calculated. as will in the art. Referring again to Figure l of the draw ing, the coil l is connected through suitable loading inductanccs (l, condenser ll, and coupling coil l,-to the detector. In the arrangement shown, this circuit F. (i, ll, I, is tuned to the frequency of the incoming signal.

The detector. shown as :1 three clcmcnt. vacuum valve M, is connected to the us cillatory circuit .l l\' coupled to coil l. The particular character ol' the dctcctor or its special circuits. is immaterial and will varv with the character and strength of the for purposcs ol length and decrement. and further. that the constants should be so related as to bring the currents flowing in the antennainto substantially exact phase. i. c.. that the dis tribution. of current in the several antcmuc should be substantially alike. The variable imluctanccs t t" and condensers l: are provided in order that the desired adjustments may readily be made: in the adjustment of the antcnmc it will be found that it is nsuallv not enough to adjust merely to the same u'are length: indeed. such adjustment may in some instances produce littlc apparent re duction of static. but by varying the ratio of the constants and coupling. \rhilc snbstantially preserving the ware length. the static noises will often disapptur or be greatly reduced. as the result of a comparatively slight change of adjustment. The range of adjustment for best results is narrow, but once found it is stable, requiring little or no manipulation to preserve it. While the use of variable elements, in each antenna, for varying both inductance and capacity is not essential, it is convenient and is the arrangement which I prefer.

The use of an intermediate circuit, as here shown, is not essential, as any other arrangement suitable for the purpose may be used, but such intermediate circuit may advantageously he employed. Neitheris it essential that the particular arrangement for combining the circuits of the two antennae here shown be employed, as any means which will permit the combination of the signal effects to produce either a stationary or a rotating resultant effect, while enabling the effects due to static to be opposed, may be used.

Referring now to the modified arrangement shown in Figure 2, it will be seen that in this modification I employ a different antenna construction, a different mode of associating the adjusting devices. and additional means for reducing static interference, which gives an important improvement in the result.

The antenmc a u are in this instance composed car: of a plurality of turns of wire insulated from one another and supported in an approximately vertical position in any suitable manner. The operation of such antennae is not different from that already described. except that larger elccllromotivc forces will be generated owing to the increased numbcr of turns if of the same dimensions, or a smaller loop may be used to obtain a sufficient electromotive force.

The mode of connecting the adjusting devices and E E is different from that shown'in Figure 1. in that coils in this instance are preferably large so; as to be always nearly equal to the total inductance of the loop antenna. and the condensers F. F. are connected across instead of in series with the loops constituting the antennae. This mode of connection is particularly advantageous where the leading-in wires are long. or when receiving shorter wave lengths than normal.

The arrangement of adjusting means shown in Figure '2 is in effect a division of the total inductance of the antenna circuit into two approximately equal inductances in parallel. thereby reducing the total inductance to one-half that of the antenn e alone. and the addition of the capacity of the con denser E as a capacity in parallel to the capacity of the leads. If these leads are long. their capacity to one another is considcrable. and in the arrangement of Figure 1 this is objectionable. and the leads should not be too close together. \Vith the arrangement of Figure 2 this capacity is notobjectionable so long as the total capacity of the antenna circuit is not too great to permit of a sufficient range of adjustment in condenser E.

Either form of antenr may be used with either arrangement. of adjusting devices.

The arrangements thus far described give a substantial freedom from static interfer time due to the hissing or sizzling" variety which I have generally found to be most prevalent and troublesome. \Vhen the ere plosive variety is present, however, there is sometimcsa suflicicnt residue, even with the most careful adjustment, to make good rece tion difficult.

y tests seem to indicate that this residue is not due, or at least not largely due, to horizontal components in the static waves or to harmonic oscillation in the antennw, but rather to the natural coupling between the two antennae. Proceeding on this assumption, I have found that by eliminating or reducing the natural coupling between the antenna. 1 am able to obtain substantially perfect elimination, even of this explosive type of static disturbance. One means of accomplishing this is shown in Figure 2, where X X are two coils so arranged in inductive relation to one another as to give a coupling effect between the two antennae circuits substantially equal and opposite to the natural coupling between the two loops. so far my tests indicate that the leads of the two antenna*,if arranged as above described, do not introduce any appreciable disturbance, and by cancelling out the natural coupling between the loops, by reverse coupling means such as the two coils X X I am able to get rid of the ordinary forms of static interference with substantial completeness.

In this connection I have found the goni-' orrictcr arrangement herein described of especial usefulness. which I attribue to the fact that the coils D I) thereof are at right angles to one another. and hence do not directly affect the coupling of the two antennas circuits to one another. Since their coupling to the coil F can. and should he made comparatively loose. the coupling between the two antennae. resulting from the mutual relation of the coil F. can also be he at small: the coils X X can therefore be use to effect a substantially complete balancing out of the coupling between the loop antennae. I believe the use of a goniometer, in a system of this kind. to be original with me and it was first described by me in an application Serial X0. 157,594. of which this applica tion is a continuation in part.

It wil be understood that coils X X are in no way dependent upon association with the particular multiple loop antenna: with which they happen to be shown in my drawing, but are available without reference to the particular antenna construction employed.

My invention is in no way limited to the use of two antennae pnly, nor is it essential that these be strictly vertical, as I have used loop antcnnzc inclined at an angle as great as forty-five degrees from the vertical, with excellent results. Also it is not essential that the several antennae should be of identical dimensions nor is it essential that they should be of the same type, although I have so far 1 ound these the preferable conditions. Variations in the above and other respects, may be made without departing' from the scope of my invention.

While I have herein s ecifically illustrated and described only loop antennae, I do not regard my invention as necessarily limited thereto, and it will be understood that even the ordinary open form with earth connection may be substituted. but for best effect in such a case, direct connected leads should be avoided, or so arranged as to be afl'ccted as little as possible by the incomin signal, as otherwise the actual separation o' the antennas is not the effective separation. In such a case also, the provision and careful use of phase adjusting means is of special im ortance.v

have shown and described my invention in the best form now known to me, but I contemplate as within its scope all modifications and equivalents whether now known or subsequently discovered, which do not depart from the essential principle of the invention, and which utilize the discoveries I have made and herein disclosed, I regard as within my invention, and claim broadly,

any means for discriminating between waves or impulses which travel vertically or appear to have a predominant vertical component and signal waves which are assumed to be waves travelling in a substantially horizontal direction and eliminating the first, while detecting the second. i

In using in my claims the word difi'erentially. I intend to designate such a combination of the ctl'ects due to static or other interference, as tends to a zero or minimum effect on the detector. whether through the use of one or more local circuits or not, and, similarly, I use the word cumulatively as designating such a combination of the effects due to the desired energy, as tends to produce an r-llcct upon the detector, B the term heterogeneous in my claims, intend to designate disturbances which do not exhibit definite wave length. but 'cause oscillations of the frequency of the antenna.

In referring to portions of the receivin system as differently circumstancerl, I mean to include either position or adjustment of the antennae, or both position and adjustment. i

in descri ing in the claims static as being vertically or nonhorizontall propagated,

it will be understood that I 0 not wish to be limited by an theory of the origin, direction, or waveike character of static, but intend to designate those disturbances which, 10 in the circuits described, act in some respects like vertically propagated waves. In describing in the claims the combining or opposing of currents, I intend to include any effect or accompaniment of such currents, as, for example, magnetic fields or electromotive forces.

In furtherexplanation of the mode of operation of the improved apparatus described herein, attention is called to the fact that when the separation of the collectors or loops is an appreciable fraction of a wave length in the line of transmission as above described, the signal current when at a maximum in one collector has a reduced ornegative value in the other collector and, therefore, the collectors operate to give different ratios of instantaneous values of static current and signal current, and it is because of this ditferent instantaneous ratio or unbalanced condition that I am enabled to balance out the static and retain the signal. In

my pending application, Serial No. 244,564,

I have described other means for producin thisdifl'erence of ratio or unbalanced cond1- 96 tion which, however, make use of this same general principle or mode of operation, and I' have pointed out in my said application that this different instantaneous ratio may be obtained independent of the dilferent 100 phase relation of the signal currents in the two collectors, that is to say may be obtained by so constructing, circumstancing,

or disposing the collectors with res act to each other, that they inherently ave a different ratio.

Having now described my invention, what I claim is: V

1. In apparatus of the kind described, a pluralit of antennae separated by an ap- I10 preciab e fraction of a wave length and connected to coupling coils disposed in noninductive relation to each other and a receiving circuit comprising a coupling coil in inductive relation to both of the first men- 116 tioned coils.

2. In apparatus of the kind described, a pluralit of antennae separated by an appreciab e fraction of a wave length and connected to coupling coils dis sad in' non- I20 inductive relation to each 'ot er, and a receiver circuit comprising an adjustable coupling coil disposed in inductive relation to each of the first-named coils.

3. In apparatus of the kind described, a pluralit of antennas located at unequal distances mm the source of signals to be received, a receiving circuit comprising a rotatable coupling coil, a plurality of coils connected to the antennas and associated 0 withthc coupling coil in such manner that currents flowing simultaneously in the coils will produce opposing effects in the coupling coil.

4. The improvement in the art of radio reception which consists in reducing the static interference at a collecting station by receiving disturbances acting as though propagated in a vertical direction and those propagated in a horizontal direction as currents of the same frcquenev but of different relative phase. and eliminating the first while detecting the last-named disturban es.

The improvement in the art of radio transmission. which consists in receiving waves due to static reaching different portions of a receiving system snhstantially si multancously. and waves of definite period arriving successively as currents of the same frequency. utilizing the relative time of arrival to dis wiminate between them and detecting the lashnanicd waves.

6. The improvement in the art of radio transmis ion. whi h consists in discriminating between wares due to static affecting different portions of a receiving! system substantially simultaneously and waves of definite period affecting these successively by combining differentially the simultaneous effects. and combining cumuiativeiy those which are successive and detecting the lastnamed effects.

7, The method of reducing interference in radio transmission. which consists in comhining in one receiving device the effects produced by static disturbances received simultaneously and definite wave length disturbances arrivin at different times in a plurality of separated antenna". and utilizing the relative time of arrival to discriminate between them by causing said device to respond more readily to disturbances of definite wave length. rc:n-hin; said antennae successively than to static distnrlianccs reaching them more nearly simultaneously.

8. The method of reducing' interference in radiot 'an inission due to stat ic disturbani'es which consists in differentiating hetwecn waves received j'roni vertical and horizontal dire tions by causing horizontal waves of the desired signal to produce clccfro-n'iotive forces in a plurality of receiving collectors having one order of phase difference. and causing those from a vertical direction to produce electro-niolive forces having; a phase difference of a lesser order. combining differentially the effects of lesser order of phase difference. combining cumulatively those of the greater order. and utilizing said last-named effects.

9. The method of reducing the effect of static disturbances. which consists in locating and adjusting a plurality of antennaa and associated circuits in such manner that static effects will produ e therein currents similar in phase and signal impulses will produce therein currents dissimilar in phase, combining differentially said currents similar in phase. and combining cumuiativcly said currents dissimilar in phase. and detccting the. presence of said last-named currents.

It). The method of reducing the effect of static disturbances in radio transmission, which consists in so relatively adjusting each of a plurality of antenna circuits as to cause currents of unlike phase to be set up therein by signals received in one, direction in a horizontal plane, and to cause currents of similar phase to be set up by disturbances propagated in a vertical direction at right angles thereto. producing a resultant magnetic field having one direction by said in phase currents, and a magnetic field having a maximum effect in a different direction by said out-of-phasc currents. and subjecting a receiving circuit to said fields so as to selectivelv receive energy from a, desired one of sai fields.

11. The method of reducing static interference in radio reception, which consists in arranging a plurality of antennae to have a directional action for horizontally received waves in a definite direction. receiving the static interference and the desired *aves in such antennae. adjusting the circuit constants thereof to cause static waves, to produce in said antenna: currents of the same phase. determining the separation of said antennae so as to cause horizontally re ceircd signal waves from the desired direction to produce l'lll'llllts having phase difference of a greater order. comhining the former differentially and the latter cumulaf ivel v in a common rccci\'in; device. and detecting the last-named currents.

12. The method of reducing static interference in radio reception. which consists in causinil the received signal to produce out. of phase currents in a plurality of collectors, causing heterogeneous dislurhaiu-es to produce currents having a different relative phase. and selcctivciv rep-"tin; the lastnamcd effects by the aid of said distinction in phase difference.

L3. The improved method of radio reception. which consists in intercepting the signal waves at two points disposed at unequal distances from the source of the waves. thereby obtaining signal oscillations out of phase with each other. combining the effect of these to produce signals, and combining the oscillations set up at the two points by static. in phase, to neutralize each other, substantially as described.

14. The method of reducing the interference in radio transmission. which consists in discriminating between highly damped heterogeneous waves, due to static disturbances and less strongly damped signal waves of definite period, b subjecting a plurality of antennae to the clients of both the hctcr0gcneous waves and the received signal waves, and adjusting the constants of the antennae so as to cause the eleotro-motive forces induced therein by the static disturbances to set up currents in said antcnme of substantially the same frequency, joining the ctl'ects in said antennas in a common circuit whegeby said static currents are opposed and their effects minimized while signal currents are combined and retained.

15. The method of reducing the interferonce with radio communication, due to atmospheric disturbances which do not behave as though possessed of either definite wave length or decrement, which consists in circumstancing a plurality of antennae so as to cause the electro-motive forces induced therein by atmos heric disturbances to set up currents of su stantially the same wave length and decrement, and to cause signal waves to set up currents of the same wave length but relatively different phase, and opposing the currents due to atmospheric disturbances in a receiver circuit to obtain substantial neutralization of said currents, while retaining the currents due to signals having definite wave len h.

16. The method of re ucing the interference with radio communication, due to atmospheric disturbances wave length or decrement, which consists in induced therein by atmospheric disturbances to set up currents of substantially the same wave length and decrement, and to cause signal waves to set it currents of the same wave length but reliitively different phase, and opposing the currents due to atmospheric disturbances in a receiver circuit to obtain substantial neutralization of said currents, while retaining the currents due to signals having definite wave length.

17. In radio signalling the method of distinguishing between impulsive disturbances, such as static, and impulses having definite wave length and small decrement, which consists in receiving both in a plurality of antenna: which are all of the same frequency, and adjusting the relative phases of the currents roduced in the circuits to minimizethe efl ect of said impulsive disturbanoes.

18. The method of reducing static disturbances in radio signalling, which consists in receiving both static and signal impulses in a plurality of antennae as a plurality of currents of the same frequency but relatively difi'erent phase, and selecting the desired current by discriminating between the phases thereof.

' 19. The method of reducingstaticinterfere which do not have as though possessed of either definite ence in radio reception, which consists in receiving static and signal waves in a plurality of antenna, disposed in a plane in} cluding the station transmitting the desired signals, and combining the currents set up in said antennae to produce in a receiver circuit effects having a ratio of static and signal currents differing from that existing in the individual antennae.

20. The method of reducing the interfer ence with radio communication due to static disturbances, which consists in causing the static impulses and signal waves to set up currents having the same frequency in a plurality of antenna, adjusting the phases of said currents, and combining them in a hommon receiving circuit, whereby the ratio between the signal currents and static currents in the common receiving circuit, is greater, than the ratio existing between said currents in the individual antennae.

21. The method of reducing the interior-- to mic ence with radio communication due disturbances,

aving the same frequency buttof different phase in a plurality of currents relatively the signal currents and static currents in the individual antennae.

which consists in causing the, static im ulSeS and signal waves to set up 22. At a radio transmission receiving statjon, a plurality of antennas effectively separated from one another by an appreciable fraction of a wave length in the direction of and means associated circuits for controllin desired reception, with said antenna the relative phases of effects produced by static disturbances in said antennae.

23. At a radio transmission receiving station, a plurality of antennae effectively as rated fromone another by an apprecia le fraction of a wave length in the direction of desired reception, means associated with said antennas for definitely controlling the relative decrement duced by static disturbances received in said antennae, and a receiving device common to said antennas. v

24. At a radio transmi' on receivingstation, aplurality of antennas etlectively se rated from one another by an apprecialil fraction of a wave length in the direction of desired reception, at common rece'ivingdevice, connections therefrom to each of said antennae, and means for definitely controlling the relative decrement and phase of 0b cillations set up in said receiving device by static disturbances in said antenna.

25. At a radio transmission reoeiving fitation, a plurality of antennae separated one another by an appreciable fraction of a wave length in the direction of desired raand phase of effects pro- 1 ccption. a common receiving device. eonncctions therefrom to said antennae, and means for bringing into accord the time periods. decrement and phase of natural oscillations in said antennae. produced hy static disturbances. a detecting means. and means for selectively influencing said detecting means li ell'ccts produced in said antennae.

2o. Means for reducing the effect of static disturbances. which comprise a plurality of antcmuc located at suitahle distances apart horizontally in a direction to he ellected successively lrv signal impulses. to produce therein currents dissimilar in phase. means for adjusting the antenna circuits so that static cll'ects will produce therein currents similar in phase. means for combining differentially said currents similar in phase. means for comhining cumulatively the currents dissimilar in phase. due to the signal impulses. and means for detecting the pres ence of said last-named currents.

21'. At a receiving station, in a radio transmission system. a plurality of antennae separated in the line of desired communication and adjusted to he ditlerently affected by heterogeneous disturbances and signals received from said desired direction. at least one of which antennae is constructed to he directive for liest reception in said direction. connection therefrom to a common receiv ing device. and means for distinguishing het \vecn said efiects.

2* .\t a receiving station. in a radio transmission system. a plurality of separate antcnnzc arranged to he differently atl'cctcdby static disturhances and signals received from a desired direction. connections therefrom to a common receiving device and a local circuit in said receiving device. and means for difi'crentially afl'ccting said circuit hy said static disturbances and cumulativ lv all'ecting it lay signals from the de sired direction.

2'), At a radio transmission receiving station. a plurality of directive antennae. the plan of each antenna living parallel to a givcu plane and the antenna heing separated anaprcciahlc traction of a wave length in thc direction of'desired reception.

Ill. .\t a radio transmission receiving station. a plurality of loop antennae separated a con idcralilc traction oi a wave length in thc direction of dc ircd reception. the plane ni tli'li limp ln ilig jizll'tlllt'l in :1 Q'lv'lll plane, a rc chlng tlcv cc. and leads tin rcfiom to sill l autumn. 7

ll. .\t a radio tran mi sion receiving stati n. a pluralit ofloop antennae separated a c nsidcrai le fra tion of a wave length in the direction of d ired reception. the plane ot Hit'l loo heing arallel to a given plane. a rc ciiiug device and leads therefrom to said antennae. the leads from each antenna l i j samilarl located with rcspc t to earth.

32. At a radio transmission. receiving station. a plurality of loop antennas arranged in a common plane and separated hy an appreciable traction of a wave length to he received \vhcrchv currents of dill'ercnt phase are produ ed in said antennas. the plane of each loop lacing parallel to said plane. a receiving device. and means For adjusting at least one of said antennze.

32$. At a radio transmission receiving station. a filuralitv f loop antenmc arranged in a common plane. the plane of each loop licing parallel to said plane. and separated a umsidcrahle fraction of a wave length to produce currents of different phase. in said antennae. a receiving device, and means for adjusting at least one of said antennae.

ill. At a radio transmission receiving station. a plurality oi separated loop antenna. a receiving device. means for adjusting at least one of said antennae. at detecting device. and means for differentially affecting said device by received energy due to hctrogcneous disturbances and for cumulativel atfecting it by energy propagated in a deli nitc direction. 3 j

:35. At a radio transmission receiving station. a plurality of separated loop antennae. a receiving device. leads therefrom to said antennae. and means for adjusting at least one of said antennae. said means comprising a plurality of adjusting devices symmetrically located in said leads.

36. A radio receiving station. a plurality of separate antennie disposed at different distances .from the transmitting station, so that the oscillations set up therein hy the signal waves will be out of phase. means for adjusting the constants of the antenna. circuits so that. oscillations set up therein by static will he in phase. means for comhining out of phase signal oscillations to produce signals. and means WllGI'PliY the inphase oscillations are made to act on the receiving apparatus in an opposite manner so as to negative each other.

37. At a radio receiving station. a plurality of separate antcnnic arranged in a common plane and connected to a common receiving device. and means for neutralizing the natural coupling of the two antenna.

39. At a radio receiving station. a plurality of separate loop antenmc arranged in a common plane and connected to a common receiving device. and means For neutralizing the natural coupling of the two antenna.

39. At a radio receiving station. a plurality of separate loop antenna separated in the line of desired communication. and coupled to a common receiving device. and means for neutralizing the natural coupling between said antennae.

40. At a. radio transmission receiving stalit) 

